Liquid detergents have traditionally been sold in opaque bottles. However, use of clear bottles can be aesthetically appealing to consumers as they can see the consistency of product, and suspended particles if they are present. However, the use of clear bottles can lead to the undesirable loss of enzyme activity (i.e., enzymes present in the liquid compositions) by UV light. By UV light is meant light having wavelength of about 250 to about 460 nanometers (nm). Specifically, UVA generally is in range 320-400 nm, UVB about 290 to 320 nm and UVC below 290 nm, down to about 250 nm.
It has been known in the art that UV absorbers can be added to the bottle material during manufacture of clear bottles to protect them from becoming brittle and to protect the ingredients inside the bottle. For instance, in GB 2228940 the use of a dicarboxylate in polyester bottles to protect contents--mainly food--from 320-360 nm is described.
In EU 0461537A2 the use of film formers for blocking UV radiation from passing through glass bottles is described. While use of such ingredients can block the transmission of UV light through clear bottles, UV absorbers for inclusion in bottle material are expensive, and must be added when bottle material is hot and molten and there is the risk of burning the operator.
WO 97/26315 (to Colgate) discloses transparent containers with specific chromaticity defined by x and y values. Specific dyes are used in the liquid to maintain the container. The reference neither teaches nor suggests transparent liquids with the specific combination of f-dyes and enzyme.
GB 1,303,810 discloses clear liquid medium and visually distinct components suspended in the medium. Detergent compositions containing f-dyes and enzyme capsule are not disclosed.
U.S. Pat. No. 3,812,042 to Verdier discloses clear packages containing liquids with a viscosity and clarity control system comprising urea, lower aliphatic alcohol and optional hydrotrope.